General purpose household cleaning compositions for hard surfaces, including metal surfaces, glass, ceramic, and other non-metallic surfaces, hard and relatively durable organic surfaces such as paint, plastic, linoleum, are available in both powdered and liquid forms. The vast majority of said hard surface and general purpose household cleaning compositions mainly consist of materials other than organic surface-active detergents, with inorganic salts as phosphates, carbonates, silicates, forming their backbone. Said compositions generally exhibit wide variations in organic-, particularly grease, and inorganic soil removal, overall cleaning, soil suspension, grease and/or wax emulsification, shine, gloss, harshness, and foaming ability, leaving on cleaned surfaces lasting films, streaks and spots which are difficult to remove, and request frequent rinsing and wiping.
Solid, general purpose household cleaning compositions consist mainly of builder salts, and inorganic builders. These compositions result in filming, even damage to some metal surfaces such as brass and silver. The common liquid general purpose household cleaning compositions contain besides relatively high amount of builder salts, fairly high amounts of solvents and hydrotropes, which compounds do not provide any detersive benefit. Some specific hard surface cleaners contain in addition special ingredients either to protect the substrate or to remove specific soils. Corrosion inhibitors are, for example, included in metal-cleaning compositions (U.S. Pat. No. 2,485,554), peroxides are added to bleach out organic stains (U.S. Pat. No. 2,576,205), and even such special metal salts as zincates, beryllates or aluminates have been proposed (U.S. Pat. Nos. 2,575,576; 2,514,304 and 2,447,297). Other specific hard surface cleaners require a special acidic after-treatment, for example with acidic solutions of fluosilicates (U.S. Pat. No. 2,656,289). Thus, achieving equal efficiency in removing both inorganic and organic soils and, in particular, greasy soil with commonly available general purpose household cleaning compositions is hardly possible. Further, any improvement on inorganic soil removal of such household cleaning compositions results in a loss on organic soil and, particularly, on grease removal, and vice-versa, while the incorporation of organic and/or inorganic builder salts to sequester the water hardness ions and to enhance the cleaning efficiency of the surface-active detergent compound yields in addition an even more pronouncd filming, streaking and spotting due to the salt residues left on the cleaned hard surfaces, spoiling the gloss of the latter if not rinsed frequently.
It has now been found that the foregoing disadvantages of common, general purpose household cleaning compositions, both solid and liquid, can be overcome by the present invention. The cleaning compositions of this invention are particularly suitable for all kinds of hard surfaces and has outstanding organic soil and inorganic soil removal properties when diluted in hard water, does not leave films, streaks, stripes or spots, and does not require subsequent rinsing and/or wiping. The foregoing is accomplished by polypeptide, i.e., a di-, tri-, or tetrapeptide, and mixtures thereof, or a specific protein hydrolysate with a selected organic, surface-active, detersive sulfuric acid reaction product or a water-soluble salt thereof.
It is surprising that such performances can be achieved with a rather uncomplicated general purpose household cleaning composition, containing only two essential components: a specific organic, anionic, surface-active, detersive sulfuric acid reaction product, and an elected lower polypeptide and mixtures thereof or a protein hydrolysate, because of the absence of detergency-enhancing builder salts and because lower polypeptides are void of any detersive activity.
The presence in general purpose household cleaning compositions of water hardness complexing and detergency-enhancing organic and/or inorganic builder salts has always been considered absolutely necessary. The substantially builder-free cleaning composition of this invention, when diluted in hard water and even in very hard water (e.g. hardness expressed in millimoles of CaCO.sub.3 per liter of 3.5 and higher), in concentrations as low as 0.5% by weight calculated on the finished product, shows excellent organic and inorganic removal performances, however, without leaving streaks, films or spots on the cleaned hard surfaces, rendering additional rinsing and/or wiping superfluous.
These performance results are the more surprising, because they are only obtained with a specific organic, anionic, surface-active, detersive sulfuric acid reaction product, chosen from the group consisting of paraffin sulfonic acid having from 12 to 22 carbon atoms; alkyl benzene sulfonic acid having from 8 to 18 carbon atoms in the alkyl radical; alkyl sulfuric acid esters having from 10 to 22 carbon atoms in the alkyl group; the corresponding alkali-metal, ammonium and substituted ammonium salts, and mixtures thereof.
Combinations of any other organic, anionic, detersive sulfuric acid reaction products as olefin sulfonic acid, ethoxylated alkyl sulfuric acid ester, alkyl glyceryl ether sulfonic acid, the corresponding alkali-metal, ammonium and substituted ammonium salts, or mixtures thereof, or nonionic, cationic, zwitterionic and ampholytic surface-active detergents with said lower polypeptides or protein hydrolysate do not yield same or similar results.
None of the combinations of any of said specific synthetic, organic, anionic, surface-active, detersive sulfuric acid reaction products, nor of any other organic, synthetic, anionic, surface-active, detersive sulfuric acid reaction product, as olefin sulfonic acid, etc., and/or nonionic, cationic, zwitterionic and ampholytic surface-active detergent combined with similar amounts (as the amounts of polypeptide or protein hydrolysate of the composition of the present invention) of either (a) organic and/or inorganic builder salts or (b) pure amino acids or (c) polypeptides having a higher molecular weight, is as effective in overall cleaning, organic-and inorganic soil removal, soil suspension and grease emulsification, non-filming, non-streaking and non-spotting as the claimed composition.
Higher aliphatic amines, and other N-containing compounds as alkyl ethanol amides, morpholides, nitrides, as well as lower acyl derivatives of higher fatty acids (U.S. Pat. Nos. 2,383,525 and 2,383,737), or amino acids and lower polypeptides, which are said to lower the surface tension of surface-active detergents (German Pat. No. 734,337), have been propsed as additives into textile detergent compositions. Also, proteins such as casein, glue, albumen, etc., which are said to be excellent protective colloids aiding in removing and segregating soil, have been proposed as textile detergent additives (Chemical Abstracts, 37, 2203). However, regardless of some similarities which exist between textiles washing and hard surface cleaning, there are fundamental differences between hard surface cleaning and textile washing, and consequently between the compositions. For example, the hard surface cleaning generally occurs with an implement, e.g. a sponge, containing a restricted amount of water. Thus, textile cleaning technology cannot be used as such in hard surface cleaning.
Liquid detergent compositions containing small amounts of partially degraded proteins, or protein hydrolysates containing polypeptides having an average molecular weight of at least 600, typically 600-12.000, as skin-protecting additives, are disclosed in British Patent specification No. 1,160,485 and in U.S. Pat. No. 3,548,056. The use of protein hydrolysates as skin-protecting agents or mildness improvers in detergent compositions is also disclosed in Canadian Pat. No. 877,909. The use of the elected lower polypeptides or protein hydrolysates of the composition of the present invention did not reveal any noticeable skin benefit either immediately or after extended use. Thus, the elected polypeptides or protein hydrolysates as used in the composition of the present invention must differ from those mentioned in said British American or Canadian patent specifications. They do differ because, as already said above, compositions contaiing applicant's specific water-soluble, organic, anionic, surface-active, detersive sulfuric acid reaction products and higher polypeptides, e.g. having an average molecular weight above 600, for example 800, 1200 and above, do not yield the same organic and inorganic soil removal properties as compositions of this invention.
Percentages and ratios are by weight unless otherwise indicated and temperatures unless noted otherwise are centigrade.